Running in the heat and humidity of the summer can be dangerous, but with these tips, you can train safely all summer long.
I don’t know about the weather where you live, but it is freaking HOT in Winston-Salem. HOT & HUMID. I love running outside but with weather like this, it can be downright dangerous (especially when pregnant!!), not to men to mention miserable. But with a few easy tweaks to your running routine, hot miles can feel a little better. And, maybe, just maybe you’ll grow to like them.
When I’m not focused on my pace (Tip #7!), I am able to appreciate just how much I’m sweating which is oddly satisfying. Did you know that as sweat evaporates it cools you down? Although, I do love my summer runs in Utah when I don’t finish my runs completely drenched!! I guess it’s fair to say I just love running, period.
Running in the Heat
Here are a couple common questions I get from readers and followers about running during the summer months.
Is it bad to run to run in hot weather?
Running in hot weather isn’t bad. But being dumb or lazy about it can be bad. Especially when you aren’t adapted to the heat. When it’s extra hot out, you sweat more, which can lead to dehydration faster. And dehydration can go very bad very quickly. You need to carry fluids (see tip #1!). There are some important things to consider when you’re ready to run in the heat, which I share more about below.
How does heat affect running?
Heat and/or humidity, simply put, make running harder. Both elements tax the body and, combined, they especially tax the body, increasing your heart rate more quickly.
That means your heart is beating harder for the same pace you’d run in cooler temps. And that means your run will feel harder and/or you won’t be able to hit your normal paces. Tommy quickly learned this last February when we visited Palm Beach, Florida, right after he took up running. (Later that summer he ran his first half marathon!)
Here’s everything I employ when running in the summer to stay safe and a little more sane!
10 tips to not hate life running in the heat
1. Carry fluids
I drink 16 oz of ice water with Nuun (for electrolytes) before I run and I carry water on my run, even for distances I normally wouldn’t. In the cooler months, I rarely carry water with me on runs shorter than six miles. But in the heat, I always run with water or Nuun. Sports drinks are great options if you don’t have Nuun. Headache, nausea and lightheadedness can be common if you aren’t careful to hydrate and eat something.
In hot temps, you will dehydrate more quickly and will need to rehydrate along the way. This is the water bottle I carry – the hand strap is key so it’s not super annoying. I keep my water bottle in the fridge so it’s cold when I head out. Ultrarunner Patrick Reagan recommends drinking about 20oz of water per hour AND consuming 200 calories. The goal with cold water before and during is to help keep your core temperate low. Patrick Reagan also recommends soaking your hat or bandana in water at the start of your run to help you stay cool.
Remember if you aren’t sweating when it’s very hot and/or humid, that’s a sign you are dehydrated. While you may not be dripping in sweat (especially if you live in a dry climate), pay attention to areas where you can confirm that you are actually sweating (e.g. hairline, waistband, bra straps). Sweating is crucial to keep you cool; when sweat evaporates from skin, it also helps remove some body heat. And if that process isn’t happening because you’re dehydrated, you’ll overheat more easily.
2. Be sure you are well fueled
Aside from being hydrated, make sure you’re fueled before you head out. Remember, all runs will feel harder in the heat so you’ll want to make sure you aren’t running on empty.
In the summer, I like a couple dates or a banana with peanut butter. Giddy Up Bites from Run Fast Eat Slow are great too – I keep them in the freezer. Cold food, cold water, happy me. Making sure you’re well-fueled is also a key to avoid muscle cramps, heat cramps, and heat exhaustion which are common in extreme heat.
3. Wear light, wicking clothing
Wear something breathable and sweat-wicking. (I have my favorite tops and shorts listed on this page.) I wear a visor most days to keep the sun off my face (a visor rather than a hat so heat can escape my head).
If I’m going for sunglasses, they’re always Goodr sunglasses since they don’t slip down my face even on my sweatiest days and the price can’t be beat.
And please, for the love of all that is good and wise, don’t wear cotton, especially if you live in a humid environment. It will trap the heat escaping from your body, hold onto your sweat, and make you hotter. If you’re careless, you could suffer a heat stroke. Be wise about what you’re wearing!
4. Wear sunscreen
After having three friends in their late 20s get melanoma, I take SPF seriously. I apply sunscreen before any run where I’ll be in the sun for any amount of time, even in the morning. I like Beautycounter Mineral Sunscreen. It doesn’t leave that crazy white cast that some zinc-based sunscreens do, it’s sweat proof and safe (for our bodies and for the reef) so it’s a win all around.
5. Plan a shady route, or run in the off hours
One of the best things you can do is run in the off hours — early in the morning or later in the evening. The sun will be much more intense from 11am-3pm and oftentimes, 5-6pm can be the hottest time of day. If you can get out early in the morning or wait until a little later in the evening, it’ll help a lot. You can check your weather app for the heat index and plan your run accordingly.
Pre-COVID, I always ran in the mornings with friends, but I also really love evening runs. When I was doing two-a-days while training for the Boston Marathon last year, I had my second easy run in the evenings and it quickly became a favorite way to unwind after a long day.
6. Start much slower than normal and expect to run slower throughout your run
In the winter, you start slowly to allow your body extra time to warm up in cold temperatures. And in the summer, you want to start slowly so your body temperature and heart rate don’t spike as early on in your run. That will help your run feel a little better for a little longer. I would even spend about 20 minutes outside before you start your run. Maybe stretch or warm up a little, but letting your body acclimate to the heat will help make sure you’re feeling good on your run.
A good rule of thumb is that your pace will be about 20-30 seconds slower than your “normal” pace. But some days, you may run 90 seconds slower. Or more. It’s ALL OKAY. Just slow down. It’s not a big deal. I promise. If it helps, brag on Strava about how much slower you can run when it’s hot – make that your claim to running fame.
And remember that EVERYONE is slower in the heat. It’s science. It’s not just you. This calculator is handy to see how the conditions will impact you on any given day. And the Dark Sky app will show you what time of day the Dew Point is the lowest. (Side note: It’s one of the few apps I’ve paid for because it’s super handy when planning runs around wind, rain, temps, everything. I find it’s more accurate than the iPhone weather app.)
7. Run by effort & take walk breaks
Run by effort, not your typical pace when it’s hot. If you have an easy day, run a pace that allows you to say complete sentences. If you have a workout, either adjust your interval/tempo pace or run the effort you should be feeling for the particular intervals. Don’t let a training plan override common sense.
And don’t be too uptight or stubborn to take walk breaks. My friends and I walk at least 3-4 times during summer runs. It’s usually only 30-60 seconds but it helps a lot to have a little breather.
If you’re not feeling strong, SLOW DOWN! And if you feel dizzy or lightheaded, STOP RUNNING IMMEDIATELY. Take the heat seriously. If you’re not feeling better after slowing down and drinking some water, seek medical attention.
Listening to your body is especially important when running during pregnancy (more on that in an upcoming post) and even more so if you’re running in the summer months while pregnant.
8. Run with someone — or tell someone your plans
If you can find a running buddy, it really makes the most miserable conditions a bit more tolerable!
If you don’t have anyone to run with or can’t safely social distance on a run, make sure you let someone know when you’re running and when you plan to be back. This is a good habit for all your runs – not just hot ones. I always let my husband know my running plans, including when I’m leaving, roughly how long I plan to run and the route I’m taking.
9. Pour Water ON your body, not just in it
The goal with this is to keep your core body temperature down as much as possible. If you ever watch elite runners during a race, you will likely see this. I pour it on my head and down the back of my neck. It might seem intense or silly, but it seriously helps! Some people swear by putting cold water on their wrists.
I employed this strategy during the 2019 Boston Marathon and it’s part of the reason I felt strong the entire race, even as temps rose.
10. Listen to your body
Bottom line – be smart. Your life doesn’t depend on hitting a certain pace or distance. But it can be life threatening if you don’t pay attention when your body is screaming at you. There will always be another run.
What’s your best advice for running in the heat? Any gear you swear by?
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